Nutritional requirements of red tilapia

摘要

Two experiments were conducted to study protein, energy and feeding levels required for optimum growth of Florida red tilapia (Oreochromis mossambicus x O. hornorum) fingerlings. In the experiment 1, a 4 x 3 factorial design was adopted to prepare 12 diets containing 4 protein levels (25, 30, 35 and 40%) each at three energy levels (350, 400, and 450 kcal GE/100 g). The diets were fed to red tilapia (0.8 g) to satiation, 3 times a day, for 60 days. Fish performance was significantly improved (P 0.05) with increasing dietary protein from 25 to 35%. At each protein level, increasing energy level from 350 to 450 kcal GE/100 a resulted in improving fish growth and feed utilization efficiency. At each dietary protein level, body lipid was positively correlated. However, both bodywater and protein were negatively correlated with dietary energy levels, and body ash was not significantly affected by dietary treatments. In experiment 2, red tilapia (3.3 g) were fed a test diet (35% cp and 4.50 kcal GE/g) at 7 feeding levels, 1, 2, 3, 4, 5, 6 and to station, three times a day for 30 days. The feeding levels required for maintenance and optimum performance were 0.77% and 5.7% BW/d, respectively. The amounts of food, protein and energy required for maintenance were 9.33, 3.27 mg/g/d and 37.3 cal/g/d, respectively. Body lipid was positively correlated, while bodywater, protein and ash contents were negatively correlated with feeding levels.